Realistically it will be difficult to get a lot more than (a genuine) 125Hp out of the engne withe the stock pump and injectors

Different rolling roads / dyno(meters) can give different results, and some exaggerate the results so you could get 140Hp "on paper" but in "real life" those horses wont be reaching the wheels, if you know what i mean

whatever you do to the turbo/ air supply/ boost pressure - the pump/ injectors will hold it back

If you have a fixed vane turbo with wastegate, you could fit an electronic boost controller - then you can run more boost and (with the right controiller) the boost should come in sooner, reducing lag, improving throttle response and increasing power/ torque at lower revs - giving you more pull out of corners

Best to fit a boost gauge and a good, matched to the engine (not too big/ not too small) front - mounted intercooler

Im sure thare are loads of remappers in Birmingham, but good ones? for you, i think you need one with premises, and their own rolling road/ dyno

Also look in to lightening the car, especially the rotating parts, like the wheels flywheel etc - you could look at my build thread for ideas

its a claimed 120PS, 275Nm, thats without turning it up, in my experience the tuning box gives more bottom end, and a remap mor top end power

not cheap at £360, but you might pick up a secondhand one, any "box for the vp30 (your rotary fuel pump) should do ok - better to get one with the plugs/ sockets attached

On another forum there was someone claiming 145Hp but i don't know what they had to do to get that power

its a good idea to do accurate performance testing/ times (safely) so you can track improvements as you do your mods, but things like timing errors and the speedo error (could be reading +10%- can make a big difference comparing your times to "official" times/ magazine times, but ok for comparing different times/ mods on the same car)

this is the Superchips Bluefin power/ torque curves for a Mk2 Focus 2.0L TDCI -

it peaks out at 3800, but it produces a claimed 176Hp and 387Nm with jusy a map, you would have to do a lot of work to get that sort of power out of your 1.8 TDCI, and it might cost a lot more to do that than just buying a mk2 and sticking a Blufin on it, you should really have a special reason to do it, like wanting to have the quickest Focus 1.8 TDDI or if you are running on veg oil etc

my wheels are stock size so speedo shouldnt be out more then normaly. at 60 my statnav read 59 and ticklers to 58

That cheap tuning box i guess puts resistence on the return signal to the ecu making engine pretending its cold ?

Im just pointing out that manufacturers/ Car magazines etc use controlled methods for timing/ speed testing cars - so in the "old days" they used a 5th wheel and a lot of gear, timimg traps etc, if you are using the speedo, it may not be accurate, if you are using a stopwatch you may press it a split-second earlier/ later, there may be a gradient on the road, or a tailwind, the methods my be different (eg - timing the 50-70mph do you sit at 50 start the stopwatch/ then throttle or accelerate from 40, then start the stopwatch as it goes through 50mph)

So it all adds up to the times you do yourself are not usually accurate, and do not compare to the official times from other cars etc

Yes the cheap tuning box connects to the IAT (intake air temp) sensor, and fools the ECU into thinking it is colder, thus increasing the fuelling, not as effective as a "proper" tuning box and tho could make one yourself for less than a fiver

the vp30 pump and the injectors are Bosch, it may be possible to obtain bigger injectors, or modify the existing injectors/ pump, there are people/ companies that do this, if you can find them, won't be cheap, though

the remap/ premium tuning box can make the most of the existing injectors, mine, for example, are running at 95% of their capacity, a remaper (even Superchips/ Bluefin) can do this, if you ask them nicely

there are things holding the engine back, different things depending on the engine there are a lot of things holding the 1.8TDDI back, you would have to change a lot to get big power - it could cost ££££££s